The government has launched an antiviral taskforce to find at least two drugs by autumn that people could take at home as pills or capsules at home to stop coronavirus infections turning into serious illness and speed recovery times.
But these will not be the first medicines to have shown promise in the treatment of Covid-19. Here we look at some that been found to help in the pandemic so far:
This is the big success story. The Oxford-based Recovery trial found last June that the cheap steroid saved the lives of one in eight people seriously ill with Covid, on ventilators in hospital. The drug, which is around 60 years old, given at low doses, is now the standard treatment for the sickest patients. It is an anti-inflammatory drug, which can dampen down the overreaction of the immune system in severe cases in response to coronavirus. Its use is thought to have saved around one million lives worldwide.
Like dexamethasone, this is an anti-inflammatory. The antibody normally used to treat rheumatoid arthritis is given by injection to block the inflammatory protein IL-6. In February, the Recovery trial published trial results showing the drug reduced the risk of death in hospital patients. Tocilizumab also shortened the length of hospital stay and those given it were less likely to end up on a ventilator. This is another re-purposed drug, and given intravenously which means normally in hospital. It has not been trialled in early-stage patients.
The asthma drug, inhaled twice a day, is the first treatment to produce good results in a trial of older people at home with Covid. The Principle trial, also based at Oxford University, found it shortened the length of illness of people over-65 or over-50 with underlying health conditions by a median of three days. It is widely available and inexpensive and now is given on a case-by-case basis to patients by GPs. Principle is the largest randomised controlled trial investigating drugs that can be used in the community, before people become so ill that they are admitted to hospital. Fewer people taking budesonide were admitted to hospital than those given other therapies, but the numbers were not significant.
This is an antiviral drug, rather than an anti-inflammatory, meaning it is designed to fight the virus at an early stage, before it has triggered any inflammation. Favipiravir is the first antiviral drug to be included in the Principle trial in people’s homes or residential homes. It has been licensed in Japan since 2014 to treat influenza. Lab and animal studies have suggested it could work in humans against coronavirus.
This antiviral has been authorised for emergency use in the US, India and Singapore and approved in the European Union, Japan and Australia for use on people with severe symptoms. It’s expensive, made by the US company Gilead Sciences, originally for hepatitis C. It was then repurposed for Ebola. It has been controversial in the pandemic, with the large independent Solidarity trial run by the World Health Organization in several countries finding it had very little effect on mortality and recommending countries not use it.
Convalescent blood plasma
This is plasma containing antibodies to the virus collected from people who have recovered from Covid-19. The US gave it emergency authorisation, but without the trials to show the effect. Although convalescent plasma has been successfully used to treat other diseases, most experts still say there is insufficient trial evidence as to how well it works and on which patients. Trials in the UK showed no overall benefit for people in hospital, but they are continuing in order to find out whether they help certain groups, such as those with weakened immune systems.